It is well known in the color photography art that color images are produced by a colored dye which is formed by a coupling reaction between an oxidized product of an aromatic primary amine color developing agent and a coupler. Various types of cyan, magenta and yellow dye-forming couplers are well known for use in such coupling reactions. The couplers are often used in combination with one or more solvents and/or other additives. High-boiling solvents which are known for use in combination with couplers include those referred to in Research Disclosure, Item 308119, December 1989.
It is often desirable in color photography to provide the coupler compounds with improved performance wherein improved performance is indicated by an increase in photographic speed when the coupler compound is employed in a silver halide emulsion color photography process, improvement in the light stability of the resulting dye and/or production of a hypsochromic hue shift in the resulting dye, or the like. For example, the Sato et al European Patent Application No. 286,431 discloses the use of pyrazolotriazole magenta dye-forming couplers in combination with phosphonates and phosphine oxide compounds in order to achieve improved dye light stability and improved dye hue. The Kato et al U.S. Pat. No. 4,171,975 discloses the use of bis-pyrazolone magenta dye-forming coupler compounds in combination with carbonamide compounds in order to achieve improved color density, developing speed, processing stability and light stability. The Nakazyo et al U.S. Pat. No. 4,900,655 discloses the use of additional magenta coupler compounds with various coupler solvents including, among others, carbonamides. The Kozo et al U.S. Pat. No. 4,840,878 discloses the use of various high boiling solvents including, among others, carbonamides, in combination with coupler compounds in short-time development processes. The short-time development processes generally take no more than 2.5 minutes, employ a reflective support and are conducted without the use of benzyl alcohol. The Furutachi et al U.S. Pat. No. 4,865,963 discloses silver halide color photographic materials comprising a pyrazoloazole series magenta coupler which is used in combination with a high boiling point organic solvent and an ultraviolet absorbent to improve light fastness and coloring.
Many coupler compositions, however, are disadvantageous in that relatively large amounts of a coupler are required to provide satisfactory color density, the reaction rate of the coupler with the oxidized developer is undesirably low, the colored image which is formed from the reaction of the coupler compound with the oxidized developer exhibits unacceptable light instability, the hue of the dye resulting from coupling is unfavorable and/or the like. It is also known that pyrazolotriazoles often exhibit speed losses in photographic systems. Accordingly, a continuing desire exists for coupler compositions of improved properties for use in color photographic materials and methods.